Process and apparatus for spray drying multi-colored detergent particles



Dec. 12, 1967 R. H.TOFFLEMIRE PROCESS AND APPARATUS FOR SPRAY DRYING MULTI-COLORED DETERGENT PARTICLES Filed Aug. 6, 1965 United States Patent PROCESS AND APPARATUS FOR SPRAY DRYKNG MULTI-COLORED DETERGENT PARTECLES Roderick Henry Totilemire, Mexico City, Mexico, as-

signor to Colgate-Palmolive Company, New York,

N.Y., a corporation of Delaware Filed Aug. 6, 1965, Ser. No. 477,820 12 Claims. (Cl. 1594) This invention relates to the production of a multicolored particulate detergent product, and particularly to a novel continuous process and apparatus for producing the same.

The invention in its preferred embodiment is primarily concerned with the continuous production of a detergent product containing in predetermined proportion discrete beads or like particles of at least two different colors, such as white and blue. Products of this type have been proposed and produced by other processes and apparatus, but the present invention provides a more reliable and less expensive arrangement, with better control of color and speed of production.

It is therefore the major object of the present invention to provide a novel process and apparatus for producing a multi-colored particulate detergent product which is less complex and more efficient than those heretofore proposed.

A further object of the invention is to provide a novel process and apparatus for producing a multi-colored particulate detergent product wherein hot fluid natural color (white) mix is spray discharged into a more or less conventional type spray tower through a series of difficult nozzles, and one or more other nozzles supply a colored discharge spray, whereby the dried spray particles of all nozzles are randomly mixed.

A further object of the invention is to provide a novel process and apparatus for producing a multi-colored particulate detergent product wherein the hot fiuid natural color (white) mix is spray discharged into a more or less ventional type spray tower through a series of different a series of spaced nozzles, and a hot fluid precolored mixture is spray discharged into the tower from a separate source in an amount proportioned to provide a desired ratio of colored to white spray particles in the spray dried product.

Another object of the invention is to provide a novel method and apparatus for producing a multi-colored particulate detergent product wherein white and colored detergent liquid are sprayed into a drying tower from similar separate nozzles, and discharge of the colored spray is periodically interrupted.

Another object of the invention is to provide a novel apparatus for producing a multi-colored particulate detergent product wherein a manifold, which may be annular, is connected to a single crutcher or like source of fluid mixed detergent composition and provided with a series of nozzles simultaneously discharging into a spray tower, and a coloring compound is concomitantly and preferably proportionately introduced into at least one of the nozzles for selectively coloring a desired proportion of the particles in the product.

Further objects of the invention will appear as the description proceeds in connecton with the appended claims and the annexed drawings which show diagrammatically an apparatus according to preferred embodiments for carrying out the process of the invention.

FIGURE 1 is a diagrammatic plan view showing a manifold and spray nozzle arrangement wherein premixed colored material is supplied to a spray nozzle not connected to the manifold; and

FIGURE 2 is a fragmentary diagrammatic view showing another embodiment wherein the coloring material is mixed into the detergent at the spray nozzle, with all of the nozzles connected to the manifold.

The invention may be carried out in more or less conventional spray drying tower apparatus, with certain modifications as will appear. For example one such apparatus is shown in the United States patent to Ledgett No. 2,851,097 issued Sept. 9, 1958 which discloses the product to be dried as continuously supplied under pressure into a ring shaped manifold, with a series of discharge nozzles extending into the tower interior. The drawings herein illustrate such an arrangement in general and it will be understood that the remainder of the tower wherein such is to be used is preferably that of said Ledgett patent to which attention is directed for any necessary further detail. Referring to the drawing in FIGURE 1 the tower wall is indicated at 11 and it supports an annular continuous manifold 12. A series of equally spaced radially projecting discharge nozzles 13-17 extend through the tower wall and are provided within the tower with similar suitable spray heads 18. All except one of these nozzles, nozzles 13-16, are connected to the manifold 12. The other nozzle 17 is separately supplied as will appear.

Hot liquid detergent composition which is mixed in suitable proportions in a main crutcher 19 is drawn through conduit 21 by a high pressure pump 22 and continuously supplied at high pressure through conduit 23 into the manifold 12, whereby the entire manifold 12 contains the liquid detergent composition at a predetermined pressure high enough to produce the required spray through heads 18 of nozzles 13-16. This composition is normally substantially colorless or white.

The nozzle 17 preferably receives its supply of hot detergent liquid from a separate small crutcher 24, through a conduit 25 containing a pump 26. The detergent to be colored is mixed independently in crutcher 24, or crutcher 24 may be supplied with colorless premixed liquid detergent from the main crutcher through a gravity flow in a conduit 27 controlled by a valve 28. Coloring material is suitably supplied from a reservoir 29 of color solution through a conduit 31 controlled by a valve 32, and crutcher 24 thoroughly premixes the detergent and coloring material to provide a homogenously colored mixture.

This colored mixture is pumped into nozzle 17 under control of a valve 33 which is preferably periodically opened and closed by a timing device 34. The timer 34 can be adjusted to vary the volume of the colored mixture discharged into the tower during any predetermined time.

In operation, manifold 12 is continuously supplied with hot colorless detergent material at pump pressure, and nozzles 1346 spray this material into the interior of the tower Where the spray dries into discrete white or colorless beads or like particles as in said Ledgett patent. The material discharged at nozzle 17 is colored and the spray dried particles therefrom are randomly mixed with the dried particles from the other nozzles as they all fall down through the tower.

The foregoing is a continuous process and it is usually desirable to keep the ratio of colored to white particles fairly low, preferably about three to four percent colored. On the other hand, it is desirable that the colored beads or like particles be of the same size, shape and type as the white particles, and for that reason all of the nozzles 1317 are preferably of the same size with identical spray heads 18. Also the flow rate through nozzle 17 may preferably be the same as through the other nozzles 13-16. In order to properly proportion the supply of colored particles, the timer 34 is set to periodically open and close valve 33. In practice thus the timer 34 usually opens valve 33 for a few seconds during which nozzle 17 3 will discharge colored spray, and then the timer closes valve 33 to interrupt the colored spray. The ratio of timer of colored spray to time of cut off may be adjusted relative to the supply of white beads from nozzles 13-16 to provide the desired ratio of colored beads in the final product.

A further embodiment of the invention is shown in FIGURE 2, wherein all of nozzles 13-17 are connected to receive hot detergent mix from the manifold 12 and means is provided for coloring the discharge of nozzle 17.

In this embodiment one of the five discharge: nozzles, nozzle 17, is modified to provide for discharge of colored material. A mixing vessel 35 contains a solution of coloring compound. Vessel 35 is connected by outlet conduit 36 and an injection fitting 37 into the discharge nozzle 17 radially inwardly of connection of the nozzle 17 to the manifold 12. A valve 38 is provided in conduit 36 and a timer device for automatically opening and closing it is provided at 41. A valve 39 may be provided in nozzle 17 between fitting 37 and manifold 12. Also a direct branch conduit 44 containing a valve 42 may be provided between vessel 35 and manifold 12.

In operation, the colorless liquid detergent composition isisupplied continuously at pump pressure through manifold 12 and all nozzles 13-17 to spray into the tower where the spray is dried into discrete beads or like particles as in said Ledgett patent. The material discharged through nozzles 13-16 dries into white or colorless beads. At nozzle 17, however, with valve 42 normally closed and valves 38 and 39 open, coloring solution from vessel 35 is continuously injected through fitting 37 into the liquid composition passing through nozzle 17. This injection may be gravity flow, by aspiration or due to pressure from vessel 35.

In any event by the time that the material in nozzle 17 is sprayed into the tower the coloring solution is homogeneously mixed with it, whereby all of the beads resulting from the nozzle 17 spray are homogeneously colored.

In practice the valve 38 may be adjusted as one way to vary the amount of coloring solution fed into nozzle 17 and thereby control the shade of coloring of the colored beads in the spray dried product. Another way to accomplish the same is to vary the concentration of color during mixing in vessel 35. The timer 40' acts periodically like that at 34 in FIGURE 1 to periodically close and open valve 39 to proportion the amount of colored beads relative to white beads in the spray dried mixture.

Optionally a timer 41 may be provided for valve 38 which proportions the timer during which coloring material is supplied to the nozzle 17.

The beads formed by spray drying are randomly and uniformly intermixed as they fall and move about during their travel through the tower so that by the time the product accumulates at the bottom of the tower it contains the colored and white particles in substantially uniformly distributed mixture.

In the disclosed embodiments all nozzles 13-17 have the same capacity and the final product will have about three to four percent colored particles. This may be varied by timing adjustments, injecting coloring at one or more of the other nozzles, by providing more nozzles to change the proportion, or by adjusting the valve to nozzle 17 to reduce the amount of discharge but retain a desired color or hue in the reduced percentage of beads.

In the embodiment of FIGURE 2, the vessel 35 may be large enough to contain enough mixed color solution for a predetermined time of operation, such as a day, or it may include means for continuously feeding color compound and carrier liquid into it for mixing and pumping through conduit 36.

While valve 42 is normally closed in FIGURE 2, for some requirements it may be desired to similarly color all of the beads for a time, and in such case valve 38 is closed and valve 42 is opened to discharge color solution directly into the manifold.

Another variation is to provide a second different color at one of the other nozzles, so that for example nozzles,

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

What is claimed is:

1. A process for continuously producing a multicolored particulate detergent product which comprises:

(1) forming a first stream of an uncolored liquid detergent composition;

(2) forming a second stream of an uncolored liquid detergent composition;

(3) forming a stream of colorant;

(4) admixing said colorant stream with one of said detergent streams to form a colored detergent composition stream;

(5) subsequently spraying said uncolored liquid detergent composition into a stream of drying gas in the form of a plurality of liquid droplets;

(6) separately but simultaneously spraying said colored liquid detergent into said stream of drying gas in the form of a plurality of colored liquid droplets;

(7) whereby said colored and uncolored liquid droplets are dried; and

(8) removing a dry particulate detergent product containing a mixture of colored and uncolored particles from said drying air stream.

2. The process in accordance with claim 1 wherein the spraying of colored detergent is periodic to provide the desired proportion of colored to uncolored particles in the spray dried product.

3. A process in accordance with claim 1 wherein the composition of said second detergent stream is identical to the composition of said first detergent stream.

4. A process in accordance with claim 1 wherein the composition of said second detergent stream is different from the composition of said first detergent stream.

5. A process in accordance with claim 1 wherein at least one of said streams of detergent is formed into a plurality of streams prior to said spraying thereof into said stream of drying gas.

6. A process in accordance with claim 5 wherein a second stream of colorant is provided to form a second colored liquid detergent composition.

7. Spray tower apparatus for continuously producing a multi-colored particulate detergent product comprising:

(1) a vertical drying tower;

(2) means for flowing a stream of heated gas through said tower;

(3) first means for feeding liquid detergent to said tower;

(4) second means for feeding liquid detergent to said tower;

(5) means for admixing a liquid colorant into the liquid detergent in one of said means for feeding liquid detergent whereby a colored liquid detergent is formed therein;

(6) means for spraying the uncolored detergent liquid at high pressure through at least one nozzle in an upper zone of said tower to form a plurality of uncolored liquid droplets;

(7) means spaced from said means for spraying said uncolored detergent liquid for simultaneously spraying said colored detergent liquid at high pressure through at least one nozzle in an upper zone of said tower to form a plurality of colored liquid droplets;

(8) whereby said sprayed uncolored and colored liquid droplets are separately formed into dry particles; and

(9) means for removing a mixture of the dried colored and uncolored detergent particles from said tower.

8. Apparatus in accordance with claim 7 wherein a mixing chamber is provided external to said tower for admixing colorant with said detergent.

9. Apparatus in accordance with'claim 7 wherein there is provided a common source of liquid detergent for said first and second means for feeding liquid detergent to said tower.

10. Apparatus in accordance with claim 7 wherein all of said nozzles are connected to one source of uncolored detergent liquid by a manifold mounted on the exterior of said tower.

11. Apparatus in accordance with claim 7 wherein means are provided for automatically varying the amount of said colored detergent being sprayed.

12. Apparatus in accordance with claim 11 wherein said means for automatically varying the amount of colored detergent material is adapted to periodically terminate the flow of said colored detergent material.

References Cited UNITED STATES PATENTS Strahan 239-306 X Ellis 159-4 X Wagner 159-4 X Young 239305 X Dreger et al. 260-402 Sartorious 3410 Boyd 202 Rotunda 239 X Bauer et a1 15941 X Grifo et al. 252- FOREIGN PATENTS Great Britain.

NORMAN YUDKOFF, Primary Examiner.

20 J. SOFER, Assistant Examiner. 

1. A PROCESS FOR CONTINUOUSLY PRODUCING A MULTICOLORED PARTICULATE DETERGENT PRODUCT WHICH COMPRISING: (1) FORMING A FIRST STREAM OF AN UNCOLORED LIQUID DETERGENT COMPOSITION; (2) FORMING A SECOND STREAM OF AN UNCOLORED LIQUID DETERGENT COMPOSITION; (3) FORMING A STREAM OF COLORANT; (4) ADMIXING SAID COLORANT STREAM WITH ONE OF SAID DETERGENT STREAMS TO FORM A COLORED DETERGENT COMPOSITION STREAM; (5) SUBSEQUENTLY SPRAYING SAID UNCOLORED LIQUID DETERGENT COMPOSITION INTO A STREAM OF DRYING GAS IN THE FORM OF A PLURALITY OF LIQUID DROPLETS; (6) SEPARATELY BUT SIMULTANEOUSLY SPRAYING SAID COLORED LIQUID DETERGENT INTO SAID STREAM OF DRYING GAS IN THE FORM OF A PLURALITY OF COLORED LIQUID DROPLETS; (7) WHEREBY SAID COLORED AND UNCLORED LIQUID DROPLETS ARE DRIED; AND (8) REMOVING A DRY PARTICULATE DETERGENT PRODUCT CONTAINING A MIXTURE OF COLORED AND UNCOLORED PARTICLES FROM SAID DRYING AIR STREAM. 